


Every little lie gives me butterflies

by PerthroSeidraikiri



Series: hold your heart the way he holds your hand [6]
Category: Ao no Exorcist | Blue Exorcist
Genre: Blood, Body Horror, Demon Familiar Rin, Flirting, Gen, M/M, Manipulation, Rough Sex, Smut, Yandere! Mephisto
Language: English
Status: Completed
Published: 2020-08-26
Updated: 2020-08-26
Packaged: 2021-03-06 19:52:59
Rating: Mature
Warnings: Rape/Non-Con
Chapters: 1
Words: 2,532
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26114464
Author URL: https://archiveofourown.org/users/PerthroSeidraikiri/pseuds/PerthroSeidraikiri
Summary: It’s nearly 3 am, and Mephisto isn’t in his room.He turns around, ready to go ask Amaimon where the man is and maybe get into a little fistfight for showing him the wrong room. But there’s a figure standing by the door, a tall, towering figure looking at him with purpose.Or Mephisto likes to keep his loved ones close.
Relationships: Amaimon & Okumura Rin, Kamiki Izumo & Okumura Rin, Okumura Rin/Mephisto Pheles
Series: hold your heart the way he holds your hand [6]
Series URL: https://archiveofourown.org/series/1774975
Comments: 14
Kudos: 54





	Every little lie gives me butterflies

**Author's Note:**

  * For [QueenOfTheNerdlords](https://archiveofourown.org/users/QueenOfTheNerdlords/gifts).



> Gave a go at Yandere! Mephisto.  
> It was quite fun XD.
> 
> Mind the tags! This fic gets a bit darker as it reaches the end.

“Where are you going?” 

Izumo’s voice always tended to be sharp sometimes, and often when she did talk in a direct and straightforward way more than she usually did, it made him flinch and go alert. Tail curling tightly against his torso and ears twitching from the acerbity in her tone.

His soles brushed against the hard concrete ground as he turned around, smiling largely, “I…” he wrinkled his nose in discomfort as her shampoo assaulted his nose, “Well. I’m going to see someone.”

“Okay... But why are you sneaking off like that?”

He looked at the unlocked door behind her, glancing at it guiltily as her question hit him, he had used the back door. They never used it unless they were taking out the trash. But it was 1 am in the morning and that would be very unlikely. 

Not to mention it isn’t his day to take out the trash.

“Uh… I wasn’t sneaking off anywhere…” he murmured, eyes trailing away from her sharp, unconvinced gaze. She probably already knows he’s lying. He’s never been a very good liar.

Not with her, not with _him,_ not with anyone. 

His tail swishes behind him, sweeping the dust on the floor as he waits for her to head back inside or do something that won’t make him feel like he had actually been sneaking out. The look in her eyes fade over to unimpressed before she waves him off.

“Just be back before sunrise okay?”

The concern in her voice melts his heart, even though the expression on her face is the exact opposite. She’s not a fan of wearing her feelings on her sleeve. But it doesn’t matter to him, he knows her as well as she knows him. 

They’re partners. 

They’re friends.

Of course she understands his situation and is perfectly fine with letting him go.   
  
He woops, thanks her with a huge hug and disappears into the streets, grin on his face wide and content.

A small disbelieving scoff leaves Izumo, but the frown that quickly replaces it speaks volumes.

__

The mansion, as usual, is intimidating. The large expanse of it doesn’t help either and neither does the eerie silence of the grounds as he jumps over the gate. Adrenaline still rushing in his veins, breath heavy from running and cheeks flushed from perspiration.

He hears his jacket rip but he keeps going, he’s too happy to care about the clothing; his mind is occupied by something else, someone else who he’s been looking forward to seeing in a week. 

It’s a long run, but when he reaches the door he swings it open and doesn’t stop. He rushes up the stairs, turning corners, grin growing even wider as he spots a familiar green spike of hair. 

“Brother!” The echo travels all through the hall, into the empty rooms that have their doors wide open (probably Amaimon’s doing). Yellow, unimpressed eyes turn to look at him then crinkle at the corners ever so slightly as his brother turns around, hands in his pocket and tongue swirling around an everpresent lollipop in his mouth. 

“Finally got away from that human?”

“Izumo,” he corrects, raspy but unperturbed, “she always lets me come over, Amaimon.”

Golden eyes roll, “You took longer than usual.”

“Yeah… I still had work to do, and missions to go on-”

Amaimon leans forward, nips his ear with after a small nuzzle, “He’s been cranky.”

Cranky is definitely an understatement. 

The mention of that though, a fact—because Amaimon doesn’t ever _not_ state facts and truths— makes his heart flutter and clench in a painful but elated way. A small little chuckle bubbles up his throats, “Ironic, cause he’s the one who sends me on all those missions…”

Lazy shoulders shrug at him, “Big brother doesn’t care about all those, you know that.”

The lollipop in his mouth makes a small _clack_ , “He’s waiting for you too.” Amaimon’s long, black clawed fingernails point to the end of a hall. At the door that lies squarely in the centre, gold square trimmings that sparkle in the moonlight, phosphorescent. 

Rin nods and hands Amaimon a hefty bag that bulges at the corner, the sweet wrappers scratching against each other before he rushes off, pulling off his jacket before going into the room.

__

It’s tidy as usual, but not because Mephisto keeps it that way. Belial does and probably always will. The television is off, the bed is made and the pillows are so proper and crisp looking it almost makes him nervous. 

It’s nearly 3 am, and Mephisto isn’t in his room. 

He turns around, ready to go ask Amaimon where the man is and maybe get into a little fistfight for showing him the wrong room. But there’s a figure standing by the door, a tall, towering figure who’s acid green eyes look down at him with a purpose that sends a tingle down his spine. 

“I was beginning to think you had forgotten about me.” the lilt in his voice makes his heart jump to his throat for a few seconds, then Mephisto steps out, clad in a waistcoat, his polka dot scarf undone and resting around his neck. He tilts his head to the side, eyes glowing even brighter, “hm?”

“No, of course not…” he mutters, taking the man’s hands in his before going on his tiptoes to reach up, tugging at the taller man’s shirt collar and pressing their lips together, humming as he moves closer; Mephisto’s arms encircle his waist, Rin feels teeth run over his lips, a hot, heavy heat accompanying them. 

“I just got busy.”

“Yes.” he replies, it doesn’t sound like he’s agreeing or acknowledging the confession at all, “no lunch together, no calls, no texts…”

He knows exactly where this is going, Mephisto’s voice gets deeper and deeper as he talks. 

“I’m here now,” he reassures, moving closer; pressing their bodies closer together.

Mephisto’s eyes look deeper into Rin’s, full of what looks close to displeasure, “For a mere few hours.”

A feeling of guilt rushes over Rin quick and swift and devours him whole. Of course, Mephisto is displeased, Rin would be too if he hadn’t seen him in a week. But he had gotten so busy, and really, he’d seen Mephisto a few times before or after missions he had with his friends.

Though those really didn’t count.

Simple hellos and farewells didn’t please him.

So in no way would it please Mephisto either.

“I… I can find a way to stay over.”

Cold hands wrap around his wrists, tightening and poking long claws into his skin before they trail upwards, cup his cheeks, “Oh no, I couldn’t do that...It’s fine.” Mephisto breathes out, breath brushing Rin’s cheek, teeth glinting as his lips stretch, “you’ll just have to make up for it, somehow…” 

Mephisto’s fangs pierce into his lips, “Let me show you just how much I missed you; your voice…” he kisses Rin’s neck, teeth pressing into the side.

Rin whimpers out a breathy sigh of his name.

“Your body.” 

Icy hands travel down his body and slide up his shirt, grazing his nipples with the tips of his claws, walking them back to the bed and pining Rin onto it, slipping off his clothes, touching him, kissing him, marking each and every single spot.

Replacing faded marks with brighter red ones.

Some purple.

“ _You._ ” he exhales, lifting Rin’s hips up and pressing against him, grinning devilishly as Rin presses back against him, his own claws digging into Mephisto’s back deep and drawing blood, painting Mephisto’s thin body with spots of crimson.

“Okay…” he stutters, breathlessly looking up at him, eyes roaming the dark rot that litters his shoulders and trails up his neck; the thinness of his torso and chest.

Yet, even though he looks weak.

So vulnerable.

Mephisto is anything but that.

He looks handsome.

Every single bit. 

Their cocks slide against each other, Mephisto pressing against him, pumping them together slow, sensually and rolling their hips closer and closer; cum beading at the tip.

Rin kisses him, messy and raw. Tongues twirling, saliva mixing and breaking apart as he pulls away. It feels so perfect at the moment, he doesn’t want to be anywhere else.

Staying by his side makes him happy.

He needs Mephisto.

And Mephisto needs him.

__

The hickeys and bites that litter his neck are properly covered and healing, but he can’t say the same for his back. It stings every time he moves, every time he sits down.

It’s a reminder.

Not a reminder of what would happen next time he didn’t visit the man.

But of who he actually belongs too.

__

The alcohol that presses against his cheek stings. However, the hiss that escapes him breaks the silence. 

“I…” Rin starts, sniffling just a bit as he tries to collect his thoughts, collect his feelings and pile them into one good and proper speech without crying and sobbing.

“Don’t.” 

Mephisto sounds angry.

Exasperated. 

“But-”

“Did you hear me?” he hisses, cupping Rin’s cheeks roughly, “don’t apologize.”

He nibbles his bottom lip, watching as Mephisto disposes of the several red-stained cotton buds. He should be feeling guilty, not Mephisto. 

It had been his fault.

He had been reckless.

He had scared the man by coming littered in bruises and only for them to get into a disagreement which escalated into a heated, angry fight and a few more bruises and scratches. 

“Samael, at least can I-”

“No,” He barks, “you cannot, I don’t want to hear you utter the beginning of the word, I don’t want to hear you _think_ about it. If anything, I apologize. Things got out of hand.”

Mephisto’s angry eyes travel to the bruise at his cheek.

The exact one he had been nursing a few minutes ago.

The one _he_ had put onto Rin.

“I’m the one-”

“Rin. Shut up. Please.”

Tears sting his eyes, he wipes at his eyes vigorously, “I’m just trying to fix-”

“And how exactly will you fix this?”

He looks at Mephisto, confused for a minute. Eyebrows scrunched up as he looks at the man trying to pick apart and figure out exactly what he means, what he’s hinting at or trying to say without saying it.

Mephisto looks at him with curiosity. 

Then it dawns on him.

“... By listening.”

“Yes and?”

“Doing what you say.”

“ _And?_ ”

“...I,” the words and replies in his head jumble together. What else? What else could Mephisto be asking for?

“... I don’t know.” he answers, finally. 

His heart beats hard in his chest; faster and faster as Mephisto makes his way back towards Rin; footsteps louder than they should be. He stops in front of Rin and tips Rin’s head back with his finger, “Repeat that.”

Rin swallows, “I… I don’t know Samael. I’m sorry-”

“Don’t finish that sentence.”

Rin’s face clouds over in confused hurt.

“Wha—What else do you want me to say?” Frustration clouded over Rin’s face, Mephisto’s fingertips tightened. He hasn’t seen Mephisto this angry in a while, this _pushy_ and adamant in some time. 

He doesn’t pull away, he sits there and accepts the pain that travels up his jaw as Mephisto finally speaks, seeming angry yet so disappointed.

“Who do you belong to?”

Rin’s eyes widen. 

Blue eyes watery and filling with so many feelings all at once.

He wraps his hand around Mephisto’s fist, slowly and gently grasping the man’s hands in his, a little smile gracing his lips.

“You.”

The smirk that takes over Mephisto’s face only serves to make him nervous.

Yet so happy to belong.

__

It hurts.

It’s cold and he flinches as Mephisto’s claws grasp his hips tighter, harder.

Blood dripping under them.

From both Mephisto and himself.

His thighs are sticky.

His breath is heavy.

Everything else feels so uncomfortable except Samael.

He drives into Rin faster, non-stop.

The cut on Rin’s side opens.

The wounds fresh once again and looking just like Mephisto’s rotting flesh.

But he doesn’t protest.

He feels so complete.

__

“You need to calm down, Izumo-chan-”  
  
“CALM DOWN!?” She hollers and shakes Shima by his collar, “I haven’t seen him for four days! He hasn’t texted me in five days and-and-”

A hand lands on her shoulder and squeezes reassuringly.

“I’m going there, I don’t care if it’s disrespectful; if it’s going to make him mad. I need to know he’s okay-”

“Izumo-” Bon starts, obviously trying to take control of the situation, to help her fix it.

But she doesn’t want to fix it.

She wants to solve it and all they seem to be doing is making her feel worse!

“He’s my best friend! If-If you think… I’m just going to sit by here and wait,” she hisses at him, at all of them, “then you can do that for me!”

She hears them calling her but she doesn’t stop.

__

The mansion is darker and much scarier than Rin had described it to be.

The flowers bloom yet look too perfect.

The paint is so fresh that the mansion looks like it was just built.

“I… Izumo-chan…”  
  
Izumo glares at Koneko, she regrets it afterward, but at that moment she has only one mission on her mind. 

_FIND RIN._

_Make sure he’s safe._

_Make sure-_

Bon swings the door open and looks at them, unsure before he steps in, a mask of courage slipping over his face as they make their way inside. Walking silently through the halls.

Cautious and over-attentive.

“D’ya know-”

She nods.

If there’s one thing Rin is good at, it’s describing.

And of course he had explained everything about Mephisto’s house from top to bottom, he had described the man himself.

How wonderful he was.

How _kind_ his bigger brother had been.

But the look in Mephisto’s eyes had always, _always_ made her uneasy.

The door down the halls glows, gold trimming not at all inviting.

__

“You know, they’re brothers… We really should be getting involved…” It’s Shima’s voice once again. His concern almost sounds like fear, but Izumo ignores him and twists the doorknob open. There’s no creak that escapes it, the sound it makes as it swings open is much worse than a creak could ever be.

It’s tidy.

It’s dark.

Not bright and welcoming as Rin had described.

It’s so tranquil that the hair on her arms raise.

“I think we should-”

Before she can turn to scold Konekomaru, a whimper pierces the silence.

They turn, quickly, eyes widening as Mephisto steps forward. Rin in his arms, bleeding and eyes barely open.

“Rin!” 

Bon holds her back as Mephisto’s grin grows wider.

They all watch in horror as Mephisto steps under the light, arms full of Rin covered in scars, cut and wounds.

“What-”

His eyebrow raises, “Oh, this wasn’t my doing.” the smirk on his face doesn’t grow, “but you really should take care not to lose your possessions.”

His acid eyes meet Izumo’s before they trail down to look at Rin who only clutches Mephisto’s shirt tighter, “Isn’t that right Rin?”

Rin gives her one look.

One look that says it all.

He nods, slowly.

Consumed by lies.

  
  
  
  
  


**Author's Note:**

> this was fun! \0\  
> writer's block is horrible...
> 
> But anyway! This is an alternate universe I suppose, Rin is Izumo's familiar here but he's still the son of Satan and is better acquainted with his brothers here.  
> If you have any questions, just ask!!
> 
> Feedback is appreciated uwu
> 
> Have a good day! stay safe :3


End file.
